不用到现场，也能做出 Remote HMI

1. 01

   在现场录制通信 log

   将 Falcon 串接在 PLC 与 HMI 之间，调用 log.record 录制一个班次的实际操作。所有点位读写都会以 JSON-RPC 格式保存。

2. 02

   在办公室回放

   把 log 带回办公室，调用 log.replay。Falcon 会按原始时序把通信重新发布到 MQTT，就像产线正在运行。

   // Topic: falcon/line-01/rpc/req
   {
     "jsonrpc": "2.0",
     "id": "replay-01",
     "method": "log.replay",
     "params": { "log": "2026-11-03_line01_shift-a", "speed": 1.0, "loop": true }
   }

3. 03

   交给 AI Agent 开发

   把需求交给 AI coding agent。Agent 会自己订阅回放数据、整理点位、编写 PySide6 代码并运行测试，出错就自动修正。

   Build a PySide6 window for "Line 01 Press".
   Data arrives as JSON-RPC notifications on MQTT topic
   falcon/line-01/event, method "traffic.observed", params.tags.
   - Show D100 (pressure, bar) as a large gauge-style number
   - Show M20 (motor running) as a green/grey status lamp
   - "Set pressure" spin box sends JSON-RPC "tag.write" for D100
     to falcon/line-01/rpc/req
   Use paho-mqtt in a QThread and Qt signals to update the UI.

4. 04

   对照回放数据验证

   运行生成的程序，界面会实时反映回放数据。调整布局、报警与数值格式，直到符合操作人员需求。

   import json, sys, uuid
   import paho.mqtt.client as mqtt
   from PySide6.QtCore import QObject, Signal
   from PySide6.QtWidgets import (QApplication, QLabel, QPushButton,
                                  QSpinBox, QVBoxLayout, QWidget)
   
   GW = "falcon/line-01"
   
   class Bus(QObject):
       tags = Signal(dict)
   
       def __init__(self):
           super().__init__()
           self.c = mqtt.Client(mqtt.CallbackAPIVersion.VERSION2)
           self.c.on_message = lambda c, u, m: self.tags.emit(
               json.loads(m.payload)["params"]["tags"])
           self.c.connect("broker.local", 1883)
           self.c.subscribe(f"{GW}/event")
           self.c.loop_start()
   
       def write(self, tag, value):
           self.c.publish(f"{GW}/rpc/req", json.dumps({
               "jsonrpc": "2.0", "id": str(uuid.uuid4()),
               "method": "tag.write", "params": {"tag": tag, "value": value}}))
   
   app = QApplication(sys.argv)
   bus, win = Bus(), QWidget()
   pressure, motor = QLabel("--"), QLabel("MOTOR")
   setpoint, apply = QSpinBox(maximum=5000), QPushButton("Set pressure")
   apply.clicked.connect(lambda: bus.write("D100", setpoint.value()))
   
   def update(tags):
       if "D100" in tags: pressure.setText(f"{tags['D100']} bar")
       if "M20" in tags:
           motor.setStyleSheet(f"background:{'#2e7d32' if tags['M20'] else '#555'}")
   
   bus.tags.connect(update)
   layout = QVBoxLayout(win)
   for w in (pressure, motor, setpoint, apply): layout.addWidget(w)
   win.setWindowTitle("Line 01 — Remote HMI"); win.show()
   sys.exit(app.exec())

5. 05

   切换到实机上线

   把 MQTT 连接改为现场 Broker，Remote HMI 即可监看真实产线；开启授权后，也能通过 tag.write 进行控制介入。

示例中的 Topic、方法与点位名称为示意，请按实际产品文档与现场点位调整。